According to Elmhurst College, the molecules in a liquid are packed closely together and make random movements, as the molecules slip past each other. As the liquid is heated, the kinetic energy increases, which causes the motion of the molecules to increase. Eventually, the motion becomes so intense that the forces of attraction between the molecules are disrupted, and the molecules break free of the liquid, becoming a gas.
Since the polarity of the molecules determines the forces of attraction between the molecules in their liquid state, different molecules have different boiling points. In water, molecules that are bonded by hydrogen bonding present a special case of polar dipole forces exerting a very strong effect to maintain the liquid state. When compared to similar molecules in Group VI of the periodic table, water has an abnormally high boiling point of 100 degrees Celsius. If water behaved as a normal polar molecule, it would boil at about -100 degrees Celsius.
According to Wikipedia, adding a water-soluble substance, such as salt or sugar, increases the boiling point of water. Even though adding salt, in this way at a palatable level, will barely make a noticeable difference, it is possible to notice the difference in boiling point by adding salt.Learn More
Thermal energy is the movement of particles within matter and is found in the sun, magma, heated water and even the human body. Heat represents the transfer of thermal energy between matter.Full Answer >
A simple explanation for heat conduction is the transfer of heat from one object to another. As a molecule in a substance is heated, it begins to vibrate rapidly, passing heat to other molecules nearby. In conduction, the hottest object is the heat source, and the coolest is the heat sink; energy moves from the source to the sink until they are equal.Full Answer >
A quasi-equilibrium refers to a quasi-equilibrium process in thermodynamics, which is a process in which the system only deviates from equilibrium by infinitesimal amounts. Quasi-equilibrium processes can be used to closely approximate real processes.Full Answer >
Enthalpy is calculated by summing up the energy changes taking place in individual steps of a chemical process. To arrive at the enthalpy changes, Hess’s law is employed. It states that the enthalpy change accompanying a chemical change is independent of the route by which the chemical change occurs.Full Answer >